Drill



Patented Dec. 27, 1921'.

5 m G t a w W A J. F. MURRAY.

Mu mu.

UNITED STATES PATENT OFFICE.

DRILL.

Specification of Letters ratent.

Patented Dec. 27, 1921.

Application filed November 22, 1920. Serial No. 425,859.

To all whom it may concern:

Be it known that Josnrn F. MURRAY, a citizen of the United States, residing at Herrin, in the county of Williamson and State of Illinois, has invented certain new and useful Improvements in Drills, of which the followin 1s a specification, reference being had to t e accompanying drawings.

his invention relates to drills and particularly to drills including bit heads.

An 0 ject of the invention is to provide a drill of this character including a bit head wherein a pilot bit and areammg bit may be securely attached to the bit head without in the end 7 of the bit head, while a bore 8 the use of fastening means such as set screws and the like.

Another object is to provide a bit head of this character wherein the pilot bit is frictionally enga ed with the reaming bit and wherein the pilot bit is provided w1th means for binding the samewithin the bit head and in engagement with the reaming bit.

Another object is to provide a bit head of this character having a pilot bit in one end P and a reaming bit extending substantially laterally of the pilot bit and through the bit head, said bit head having a slot into which the end of the pilot bit extends where by means may be applied to the end of the 11053 bit to disengage the same from the bit A still further object of the invention is to rovide a bit head of this character inclu ing a bore in one end and a slot extending laterally of the inner end of the bore and the bit head and a slot extending obli uely of the bit head and intersectin the rst mentioned slot and the bore, sai

first mentioned slot being ada ted to receive a drift pin by means 0 which the ilot bit is forced from the bit. head and isengaged from the reaming bit disposed in the second mentioned opemn With these andother objects in view, the invention consists in the improved construction and arrangement of parts to be hereinafter more articularly described, fully claimed and i1 ustrated in the accompanying drawings, in which Figure 1 is a longitudinal sectional view of a bit head constructed in accordance with an embodiment of the invention, 7

Fig. 2 is a longitudinal sectional view illustrating the manner of unfastening the bits from the bit head, the bits being disposed in a position to be readily removed from the bit head,

Fig. 3 is a longitudinal sectional view taken on the line 3-3 of Fig. l, the pilot bit being shown in dotted lines,

lcilig. 4 is a side elevation of the pilot bit, an

Fig. 5 is a plan view of the reaming bit.

Referring to the drawings, 5 designates a bit head having the usualbit ribs 6. This bit head may be of any length desired and relatively large in diameter. A substantially rectangular and tapering bore is provided is provided in the central. portion of the end 9. The inner end of the bore 8, terminates at the intermediate portion of the bit head and is tapered longitudinally thereof. A slot 10 is provided in the bit head 5, at its intermediate ortion, said slot extending laterally of the bit and through the inner end of the bore 8, the purpose or which will be hereinafter described.

A slot 11 is provided in the head 5, said slot extending obliquely of the bit head and intersecting one side portion of the bore 8 and the inner end thereof, and the inner side wall of the slot 10. By this novel construction, the bore 8 and slots 10 and 11 communicate with each other so that any implement or object inserted in the slots or bore, will project slightly through the communicating openings in the slots or bore.

In order to pilot the bit head in the drill.- ing operation, a novel form of pilot bit 12 is rovided, said bit being 01 the twist type am. having its cuttin edge bifurcated as at 1.3. The shank let 0% the bit 12 is tapered toward one end, said end having a reduced extension 15 projecting therefrom, the shoulders 16 formed by the extension gradually inclining from the shank and merging with the extension. These shoulders form guides for the bit 12 when the same is being applied to the bit head. One side portion of the shank 14, is provided with a plurality of longitudinal teeth or ribs 17 which terminate at the adjacent shoulder 16 of the extension. When the pilot bit 12 is inserted in the bit head, the extension 15 is guided by the end portion of the bore 8 and by the shoulders 16 into the slot 10. The outer wall 18 of the slot 10 is disposed adjacent the interthe slot 10, end as the slot s same time slightly forcing it toward the siot 11. By tins novel arrangement the firmly secured within the bit head. a or course obvious that as pressure is e. L to the blt heed the bit will be more ".r nlv forced lnto the same.

In connection with the hit hes l and nilot I i p n but a novel rorm or reaming bit 19 18 used, said blthevin a plurality of obliquel disposed ribs or teeth 20 on one side thereof, the end of the bit belne' curved or extender 3 toward he side lIlOlUCllRD the eth 20.

in use, the reaming bit 19 is first disposed in the obliquely erztend' slot 11 with the teeth 20 thereof projecti through the communicating opening of th slot with the bore 8. The pilot bit 12 is then in the bore 8, with the ribs or teeth 1'? engaging the channels formed between the teeth 20 of the reaming bit 19.

described, so as to bind the some therein and also cause the bit to iriotionully engage the reaming bit 19 and maintain the same in position throng cooperation of the teeth 1? and 2-". .Vhen in this aosition, it is of course obvious that the extension 15 projects a. considerable d'stenee inwardly of i relatively long, there is no danger of: the extension coming the slot and the incontact with the end well of hnntln the fZ'lCtlOllZLl er egeinent oi the L) b k1 pilot bit with the bit heed.

When it is desired to unt'nsten or loosen the reaming bit and pilot bit to permit re movel of the seine from the bit head 5., 9. novel "form of drift pin 9 is 11. ed, said pin including tapering" sides, whichi at one end thereof. This pin is inserted in the slot 10 until one of the sides comes in contact with the end of the extension 15. sure is then apgalied to th pin, by striking a blow on the broad end thereof. This causes one side 01" the pin to engage ..-e end well of the slot 10 while the other side and forces the extension 15 outwardl of the slot 10 and into the bore 8, whereupon the pilot bit 12 may be readily removed from bore 8. T he reaming hit 19 is also reino ied from the slot 11, after the frictional engagement of the pilot bit 12 with the hit head has been relieved.

From the foregoing it will be readily seen that this invention provides :1 novel form of drill or hit head wherein the various bits may be readily applied and removed withoutthe use of fastening means such as set screws, bolts or the like, the fastening means for th bits being provided h the tapering form of the shank i4 oi the pilot hit and the The plot bit is, then forced firmly into the bit head as above novel arrangement of the slots '10 and ii. In this way, the min of the drilling OlHI'iw tion is not centered on any \rcult structure such as set screw but the entire bit is so positioned that it receives the burden oi the drilling); operation so th.- r desired amount oi? pressure may be ".pplied without danger of loosening; the hit in the hit head. On the other hand, when it is desired to remove the bit all that is necessary is to insert the drift pin til lino the slot 11, whereupon the bits may be rezulily removed with 'ing; of time and GllGlQ')". "hetis claimed is device of the character described comprisin body member loving 1?. bore in one end thereof, and slots extendingluterally of the bod, member, said slots intersectine; each other e. c. the bore, a reaming bit disposed in one o slid slots, and :1 pilot hit disposed in and trictionelly bore engaging the res nine; bit.

2. device of the character described comprising; at body member having: :2. bore in one end, the inner end portion oi said bore terminating; adjacent the iutm'mcd utc portion of the body member. said body member having a pnir oit ntern .l g (.Tl'OIK iIEfI slots. suid slots int "f ezv'h other and the bore, a. pi ot 7; reduced (JZi'UYL sion on one end. Jl ti be ddsnosrd in the bore, and u l dispi'isi l in one or s end onc ugi ed with the side Portion .1. hit the ci tension oi" the pilot bit bto extend into the remaining;- slo o psir to cause 'l'riotionol onoioo emen i the pi t bit with the r e room body 1113111l3(9. snl ti 5 bit.

hood. of the ohurncl'er described r 1 body member baring! bore 'I it on 'o, bore terminating at the intermediate portion of the body member. said i 5' member elso heriue on o liquely oxtenduzgz; slot, one side of the slot intersecting; "o rtiou oi the bor and lstorully slot into the inner end of he obliquely r :1 tapered. the end of (till eterullr o l it disposhd in 2 (Elf u ged into odv member Muir ot the Curling H ogeznont with i inediulu of l the s.

4:. it. drill of the eherioter described om bodying :1 body member, u pilot int and a reaming u. pilot bit msposed in one of raid '1 1H) bores, said bits havin longitudinally extending teeth on the ank thereof, and a reaming bit dis osed in another of said bores, said reamm bit havin a series of teeth extending ob iquely of t e shank of the bit whereb the movement of the reaming bit after t e bits are positioned in the bod member, will cause binding engagement of t e teeth of one bit with the teeth of the opfiosite bit.

testimony whereof I hereunto affix my signature.

JOE F. MURRAY. 

